In recent years, apparatuses called FAIMS (Field Asymmetric Ion Mobility Spectrometers) have been subject to attention as a technology for detecting and analyzing chemical substances with high sensitivity. Such apparatuses use a minute filter to detect changes in mobility of ionized chemical substances caused by changes in a DC voltage and an AC voltage applied to a sensor and are capable of specifying chemical substances according to the differences in the detection results.
Japanese Patent Publication No. 2008-508693 (WO2006/013396) discloses an ion mobility spectrometer having an ion filter in the form of at least one ion channel with a plurality of electrodes. With this ion mobility spectrometer, it is possible for a filler to selectively admit ion species according to a time-varying potential that is applied to conductive layers. Such potential has a drive field component and a transverse field component, and in a preferred embodiment, the respective electrodes contribute to the generation of components of both the drive field and the transverse field. Such device may be used even without a drift gas flow.